topic Cache Locking on Pentium Processor Family? in Intel® Integrated Performance Primitives

Cache Locking on Pentium Processor Family?

arintel1 — Mon, 27 Dec 2004 21:13:39 GMT

Hi everybody,

I'm Arintel. I'm new to this forum.

I'm looking for a document on how to implement Cache Locking (including data & instruction cache locking and code sample) on Pentium Processor Family.

It should be similar to the documents I found below, which are for CPU 80321 and XScale micro-architecture:

http://www.intel.com/design/iio/papers/27387202.pdf
(section 4.5 and appendix C)

http://www.intel.com/design/intelxscale/27347302.pdf
(section 6.4 and its examples)

Can someone tell me how to get it or where to buy it?
Can I possibly find it in Early Access to Intel Platforms Program ?

Thanks sincerely,
ARINTEL

Re: Cache Locking on Pentium Processor Family?

Vladimir_Dudnik — Thu, 30 Dec 2004 21:50:10 GMT

HI, I recimmend you to take a look on

http://developer.intel.com/design/pentium4/manuals/index_new.htm (document number 248966).

Regards,
Vladimir

Re: Cache Locking on Pentium Processor Family?

arintel1 — Thu, 30 Dec 2004 23:25:20 GMT

Hello vdudnik,

Thanks for your reply.

I have skimmed through all IA-32 manuals before but I found no detailed discussion of Cache Locking. Or did I miss something?

I expect something very similar to the sections in the documents that I mentioned.

Regards,
ARINTEL

Re: Cache Locking on Pentium Processor Family?

Vladimir_Dudnik — Fri, 31 Dec 2004 22:18:25 GMT

Hi,

I'm sorry, that's right. Intel Pentium family processors do not support cache locking feature.

Regards,

Vladimir

Re: Cache Locking on Pentium Processor Family?

arintel1 — Fri, 31 Dec 2004 22:28:34 GMT

Hello Vladimir,

Are you sure Intel Pentium family processors do not support cache locking feature? Or are the documents confidential?

If they do not support cache locking, is there any way to ensure high stability in execution time on those CPUs?

Thanks a lot,
ARINTEL

Re: Cache Locking on Pentium Processor Family?

Vladimir_Dudnik — Fri, 31 Dec 2004 22:41:26 GMT

Hi Arintel,

as far as I know, IA32 processors do not support cache locking, that's only feature of Xscale processors. So, there is no way to ensure that data will be locked in cache.

BTW, Happy New Year, why you are online at 31 Dec:)

Vladimir

Re: Cache Locking on Pentium Processor Family?

arintel1 — Fri, 31 Dec 2004 22:59:53 GMT

Hi Vladimir,

Happy New Year. :)

Do you know how to ensure high stability in execution time on IA-32 processors?

Thanks a lot
ARINTEL
P.S. I'm always online. :)

Re: Cache Locking on Pentium Processor Family?

Vladimir_Dudnik — Fri, 31 Dec 2004 23:05:51 GMT

I'm recommend you to read Intel Pentium 4 Software Developer's Manual and IA32 Software Optimization Guide. There is some hints how to arrange memory accesses to take advantages of hardware prefetching mechanism in available Intel Pentium 4 processors and to achieve better performance.

Vladimir

Re: Cache Locking on Pentium Processor Family?

arintel1 — Fri, 31 Dec 2004 23:07:22 GMT

Hi Vladimir,

Would you look into this document?
http://faculty.cs.tamu.edu/bettati/Courses/663/Fall-2004/Slides/DataCachesMultitasking.pdf

On page 2 it says "Cache locking is available in ...., Intel x86, ..."

Intel x86 is one of IA-32 processors, right?

ARINTEL

Re: Cache Locking on Pentium Processor Family?

Vladimir_Dudnik — Fri, 31 Dec 2004 23:17:41 GMT

M-m-m, I read about something similar in Pentium 4 Dev Guide, that's available only for special processor's states, with special memory pages attribute. In other words, it is unavailabe under Windows OS. You definetely need to study processors manual to take advantage of this feature (if it is possible) for your own hw board design.

Vladimir

Re: Cache Locking on Pentium Processor Family?

arintel1 — Fri, 31 Dec 2004 23:28:43 GMT

Hi Vladimir,

Could you please give me the link to the particular document and section that discuss about those special processor's states?

Thanks sincerely,
ARINTEL

Re: Cache Locking on Pentium Processor Family?

Vladimir_Dudnik — Sun, 02 Jan 2005 08:30:27 GMT

Hi,

As I mentioned you before, my recomendation is to read IA-32 Intel Architecture Software Developer's Manual (it is the most complete source of Intel 32-bit Architecture features), and in particularly, please take a look on Volume 3: System Programming Guide, Chapter 10 - Memory Cache Control. Article 10.5.3 Preventing Caching describes how to disable caching.

Regards,

Vladimir